At least 29 people were killed and more than 100 injured Saturday in serial blasts that rocked the western Indian city of Ahmedabad, officials said. A series of 16 coordinated bomb attacks, some of them targeting hospitals, were set off a day after seven similar blasts struck the southern information technology city of Bangalore, with an eighth bomb found and defused by the police. Indian television channels said their received emails from a little-known Islamist group calling itself the “Indian Mujahedeen” in which it claimed responsibility The same group claimed responsibility for eight bombs that killed 63 people in the western city of Jaipur in May. The bombs were detonated with timer devices and all went off in the space of 36 minutes, officials said, and up to four of them targeted medical facilities. There were two separate series of bombings, the first near busy market places. A second quick succession of bombs went off 20 to 25 minutes later around a hospital, where at least six people died, police said. Most of the blasts took place in the narrow lanes of the older part of Ahmedabad, which is crowded with tightly packed homes and small businesses. Narendra Modi, the chief minister of Gujarat state where Ahmedabad is located, said at least 16 small bombs went off Saturday evening in several neighborhoods of the busy city. Modi called the blasts “a crime against humanity,” adding that the attacks appeared to be masterminded by a group or groups who “are using a similar modus operandi all over the country.” A police spokesman said 29 bodies had been recovered and more than 100 people admitted to hospital. Many were hit by flying nuts, bolts and ball bearings packed into the bombs that were clearly designed to cause maximum casualties. Gujarat's governor, Navin Kishore Sharma, told the CNN-IBN television network that the toll was going up “every moment.” “The land of Mahatma Gandhi has been bloodied by terrorists whom we shall not spare,” said Narendra Modi, the firebrand chief minister of Gujarat state -- the birthplace of India's independence hero and one of the country's wealthiest. Distraught relatives of the wounded crowded the city's hospitals and television channels showed video footage of police officers and sniffer dogs scouring the areas that were hit. Ahmedabad is the main city in the communally sensitive and relatively wealthy western state of Gujarat, scene of deadly riots in 2002 in which 2,500 people are thought to have died, most of them Muslims killed by rampaging Hindu mobs. India had sounded a nationwide alert on Friday after the blasts in Bangalore. “We are surprised that despite a high security alert sounded yesterday after the bomb attacks in Bangalore, the blasts occurred today in Ahmedabad. We are shocked,” India's Junior Home Minister Shakeel Ahmed said in New Delhi. “It seems there is a lack of coordination between (federal) intelligence agencies and people involved in the policing,” he said. An Indian security expert and former head of the country's foreign intelligence service, B. Raman, said he feared a communal backlash in the city, where tensions from the 2002 violence still linger. Indian Prime Minister Manmohan Singh condemned the serial attacks, and urged Ahmedabad residents to remain calm, his office said in New Delhi.